In life, evolution has molded us into reproductive machines. If we are here, it is because every single ancestor before us had sex. It is no coincidence that each direct ancestor has had sex for over five hundred million years.
For a machine to have sex, you need only program it to perform the action. For a biological organism shaped and affected by sights, sounds, smells, tastes, and thoughts, it is more complicated than simply programming the action to occur at some interval “x.” This is where a barrage of chemical signals come in and alter physiological and neuronal processes. But how to release these chemicals, these hormones that will drive our machine to its ultimate purpose?
Before we get to that, we need a set to create a direct sense of euphoria among our bag of neurons, and we need a set to release that first set. This euphoria must be associated with the contemplation and action of reproduction. Yes, that set of chemicals causing random neurons to light up could be randomly associated with “good” or with “bad.” But barring an error in development, any set of neurons that associated our supposed euphoric hormone with “bad” did not then command the body to have sex. And without sex, it did not replicate. And if it did not replicate, we do not exist. Therefore, throughout our 500 million year line of ancestry, our parent organisms felt euphoria during sex and during contemplation of sex.
Although recall of your previous sexual euphoria can drive you to have sex again, a far stronger evolutionary technique exists in order to make sure you have sex. Your body rewards you for thinking about having sex. For many, the thought of sex is more exciting than the sex itself. Merely contemplating sex makes you happy. This is important because you as a machine are not programmed to go have sex because once you start you realize how happy this makes you feel (and then you don’t stop until it kills you). A machine won’t be able to easily traverse the step from “starting” to “doing.” It only does. Thus, you must be rewarded just for thinking about sex. And this thought will then bring you to the action itself.